HP 3000 Manuals HP 3000 Manuals
HP C/XL SCANU Function: Scan Until
/*******************************************************************
SCANU SPL SCAN UNTIL
This emulates the SCAN until statement in SPL, for example:
NUM := (SCAN B1 UNTIL TEST, 0);
T := TOS; <<test word -- unchanged>>
@S1 := TOS;
This may be converted to C with:
LEN := SCANU(B1,TEST,0,&S1);
The parameters to SCANU are:
ba -- The address to be scanned.
test -- The testword, two bytes. The first is the
terminate character, the second is the
test character, either of which will
cause the scanning to continue.
sdec -- The SPL stack decrement. In this context, the
value of this parameter will determine if the
function accesses the last parameter,
as follows:
sdec = 2 -- Ignore the last parameter. This
parameter need not be present.
sdec = 1 -- Expect one parameter after this:
scan_addr.
sdec = 0 -- Same as 1. In SPL, an sdec of 1
or 2 deletes the test word from
the stack, which is always unchanged
after the SCAN operation.
scan_addr -- The address of the char which stopped the SCAN
operation. This equals either the terminal or
the test character.
The return value of this function is the number of bytes moved.
********************************************************************/
short int SCANU(ba,test,sdec,scan_addr)
char *ba, **scan_addr;
unsigned short test;
int sdec;
{
char termc, testc, *temp;
temp = ba;
termc = (char)test >> 8;
testc = (char)test & OxFF;
while ((*ba != testc) && (*ba != testc)) ba++;
switch (sdec) {
case 0: ; /* fall through to case 1 */
case 1: *scan_addr = ba;
case 2: ; /* nil */
}
return(ba-temp);
}